TRAPPIST-1 Star System Revisited

TRAPPIST-1 Planet Lineup – NASA Illustration

We commented in a previous post about extra-solar planets (planets orbiting other stars), and whether those planets could have life on them. The media seem to convey the idea that there are hundreds of “earths” all containing life-forms similar to us. They suggest that if there are many Earth-like planets with life on them, then that indicates that Earth and the life on it came about by chance processes. In February, NASA called a special news conference to announce that they had found a star they call TRAPPIST-1 which had seven Earth-sized planets orbiting it in the “Goldilocks Zone.” The Goldilocks Zone is the area where water could exist in the liquid state. Many media sources were quick to announce that NASA had found seven planets that were “Earth twins” and almost surely would be inhabited.

Let us emphasize again that finding life in space is not an issue of whether God exists. If scientists find life in space, it will have been created by God and will have a purpose in existing. This particular find, however, is just another example of how quickly and irresponsibly the media will jump to promote an agenda that will sell. As more data has become available, it is becoming increasingly obvious that this seven-planet system is not an ideal place for life. In fact, any life form that happened to be there would be destroyed by the properties of the system.

TRAPPIST-1, the star that serves as the “sun,” is a very cool dwarf star. That means it gives off a very limited spectrum of light. The critical wavelengths required for photosynthesis and chemosynthesis are simply not present. The masses of these planets range from .4 to 1.4 times the mass of Earth. That means the smaller planets will almost surely not have an atmosphere since they are smaller than Mars. The length of time for the planets to orbit their star varies from 1.5 days to 20 days. That makes a very short year. They are all less than 6 million miles from their parent star. That means all activity on the star would likely be lethal to life-forms on the planets. For a comparison, Mercury, the planet closest to our Sun is separated from it by 36.8 million miles. Earth is 93 million miles from the Sun.